Electrodeposited copper foil with a carrier foil has hitherto been used as a basic material for the manufacturing of printed wiring boards which are widely used in the field of the electrical and electronic industries. In general, electrodeposited copper foil with a carrier foil is bonded to a polymer insulating substrate, such as a glass-epoxy substrate, a phenol substrate and a polyimide, by hot pressing forming to form a copper-clad laminate, and is used in the manufacturing of printed wiring boards.
Electrodeposited copper foil with a carrier foil prevents wrinkles from occurring in the copper foil during hot press forming, thereby preventing the exudation of resin from copper foil cracks initiated by wrinkle portions and from a prepreg. Also, electrodeposited copper foil with a carrier foil is receiving attention as epoch-making copper foil which solves such problems as described above and can prevent foreign matter from mixing onto the copper foil surface until the completion of hot press forming.
In general, this electrodeposited copper foil with a carrier foil is broadly divided into the peelable type and the etchable type, and it is known that in the bonding of the electrodeposited copper foil to the carrier foil, an inorganic or organic adhesive interface layer is provided. For example, there are electrodeposited copper foil with a carrier foil having an inorganic adhesive interface layer of oxides, sulfides, etc. of Cr, Pb, Ni, etc. and electrodeposited copper foil with a carrier foil having an organic adhesive interface layer of nitrogen-containing compounds, sulfur-containing compounds, carboxylic acid, etc. (refer to the Japanese Patent Laid-Open No. 2000-309898), and there are many types of electrodeposited copper foil with a carrier foil.
Incidentally, recent years have seen increasing requirements for the downsizing of electronics and electric machinery and apparatus without showing any sign of an end to this trend, and multilayer design of printed wiring boards, which are the basic parts of electronics and electric equipment, high density design of copper foil circuits, and high density packaging design of mounted parts have been required more strongly than before. For this reason, it has been strongly required that recent copper foil provide properties which can easily realize ultrafine pitches in the etching during the manufacturing of printed wiring boards and also enables the multilayer process to be easily performed.
The hitherto used electrodeposited copper foil with a carrier foil permits the formation of fine circuits, because it can be formed into a copper-clad laminate without causing wrinkles etc. to occur in its very thin electrodeposited copper foil. However, recent printed wiring boards are strongly required to permit the formation of finer-pitch circuits. In order to form fine circuits which have further advanced in comparison with conventional one, it is thought that there is room for improvement not only in conventional electrodeposited copper foil, but also in conventional electrodeposited copper foil with a carrier foil. The present invention has been made under the circumstances as described above and has as its object the provision of electrodeposited copper foil with a carrier foil which permits the realization of fine circuits of such a level as might not be realized with conventional electrodeposited copper foil with a carrier foil and which also enables the multilayer process to be easily performed.